<!DOCTYPE html>
<html class="reftest-wait">
<link rel="author" title="David Shin" href="dshin@mozilla.com">
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1879731">
<link rel="match" href="collapsed-border-partial-invalidation-001-ref.html">
<meta name="assert" content="Invalidating part of a border-collapsed table keeps border styling correctly.">
<style>
table {
  border-collapse: collapse;
}

.group {
  border-left: 1px solid black;
  border-right: 3px solid black;
}
</style>
<table>
  <tbody id="table">
    <tr><td class="group">X</td></tr>
    <tr><td>X</td></tr>
  </tbody>
</table>

<script>
onload = function () {
  // Make sure the table layout is flushed
  table.getBoundingClientRect();
  const tr = document.createElement('tr');
  const td = document.createElement('td');
  td.innerText = "X";
  tr.appendChild(td);
  table.appendChild(tr);
  document.documentElement.className = "";
}
</script>
</html>
